kern/trapentry.S

   1 /* See COPYRIGHT for copyright information. */
   2
   3 #include <inc/mmu.h>
   4 #include <inc/memlayout.h>
   5 #include <inc/trap.h>
   6
   7
   8
   9 ###################################################################
  10 # exceptions/interrupts
  11 ###################################################################
  12
  13 /* The TRAPHANDLER macro defines a globally-visible function for handling
  14  * a trap.  It pushes a trap number onto the stack, then jumps to _alltraps.
  15  * Use TRAPHANDLER for traps where the CPU automatically pushes an error code.
  16  */
  17 #define TRAPHANDLER(name, num)                                          \
  18         .globl name;            /* define global symbol for 'name' */   \
  19         .type name, @function;  /* symbol type is function */           \
  20         .align 2;               /* align function definition */         \
  21         name:                   /* function starts here */              \
  22         pushl $(num);                                                   \
  23         jmp _alltraps
  24
  25 /* Use TRAPHANDLER_NOEC for traps where the CPU doesn't push an error code.
  26  * It pushes a 0 in place of the error code, so the trap frame has the same
  27  * format in either case.
  28  */
  29 #define TRAPHANDLER_NOEC(name, num)                                     \
  30         .globl name;                                                    \
  31         .type name, @function;                                          \
  32         .align 2;                                                       \
  33         name:                                                           \
  34         pushl $0;                                                       \
  35         pushl $(num);                                                   \
  36         jmp _alltraps
  37
  38 .text
  39
  40 /*
  41  * Lab 3: Your code here for generating entry points for the different traps.
  42  */
  43 TRAPHANDLER_NOEC(divzero_entry, T_DIVIDE);
  44 TRAPHANDLER_NOEC(debug_entry, T_DEBUG);
  45 TRAPHANDLER_NOEC(nmi_entry, T_NMI);
  46 TRAPHANDLER_NOEC(brkpt_entry, T_BRKPT);
  47 TRAPHANDLER_NOEC(oflow_entry, T_OFLOW);
  48 TRAPHANDLER_NOEC(bound_entry, T_BOUND);
  49 TRAPHANDLER_NOEC(illop_entry, T_ILLOP);
  50 TRAPHANDLER_NOEC(device_entry, T_DEVICE);
  51 TRAPHANDLER(dblflt_entry, T_DBLFLT);
  52 TRAPHANDLER(tss_entry, T_TSS);
  53 TRAPHANDLER(segnp_entry, T_SEGNP);
  54 TRAPHANDLER(stack_entry, T_STACK);
  55 TRAPHANDLER(gpflt_entry, T_GPFLT);
  56 TRAPHANDLER(pgflt_entry, T_PGFLT);
  57 TRAPHANDLER_NOEC(fperr_entry, T_FPERR);
  58 TRAPHANDLER(align_entry, T_ALIGN);
  59 TRAPHANDLER_NOEC(mchk_entry, T_MCHK);
  60 TRAPHANDLER_NOEC(simderr_entry, T_SIMDERR);
  61
  62
  63 /*
  64  * Lab 3: Your code here for _alltraps
  65  */
  66 _alltraps:
  67         pushl %ds
  68         pushl %es
  69         pushal
  70         movl $GD_KD, %eax
  71         movw %ax, %ds
  72         movw %ax, %es
  73         pushl %esp
  74         call trap
  75         pop %esp
  76         popal
  77         popl %es
  78         popl %ds
  79         iret
  80